Refrigerating system



Maya?, 1930.` T.' M. G'UNN REFRIGERATING SYSTEM Filed Jan. 29, 1924 INVENTOR M,M+M

Patented May 27,: 1930Y vUNITED STATES PATENT `oi-*Fica THOMAS I. GUNN, OF BBUOKLYN, NEW YORK, ASSGNOR F ONE-SIXTH TO GORHAK CROSBY,`0IF GLEN RIDGE, NEW JERSEYv REFBIGERATING SYSTEM I Application filed January 29, 1924. Serial N0. 689,209.

My invention relates to improvements refrigerating systems and more particularly to refrigerating systems wherein a refrigerantiscompressed and liquefied in onepart of the system and is caused to va orize in the refrigeratinv or coolingy part o the sys'- tem, and the refrigerant is one in which the 4 lubricant used in the compressing means is soluble.

In refrigerating systems where Aa refrigy erating agent is compressed by a compressor and liquefied and then permitted to vaporize and expand to effect the cooling it is found v that more or less of the lubricating oil used in the compressor becomes mixed with the nrefrigerant and is carried along thereby into the refrigerating coils of the system, from which it lmust be y'periodically removed. Vhen a refrigerating agent, such as ammonia, is used in which the lubricant is not soluble, the lubricant'settles out at the bottom in various parts of the system and may be practically separated from the refrigerant by simply drawing it olf. When, however, a refrigerant is used, such as ethylor methyl chloride, ether, methane, propane, alcohol, etc., in which the lubricating oil is more or less-soluble, removal of the lubricating oil\ therefrom is attended with great difficulty. This has been done by withdrawing the 1ubricant laden refrigerant from the system and when a suitable amount 'has been collected, dis'tilling the refrigerant from the lubricant 'and returning one or both to their respective parts of the system or otherwise clisposing thereof. This necessitates expensive additional apparatus and labor and involves l the collection and accumulation of substantial quantities of lubricant in the refrigeratingcoils which considerably reduces the efficiency of the system.- l l According to my invention I provide for the substantially continuous removal of lubricant from such refrigerants and 1n a simple and eiicient manner. lFurther and 'more specific objects,- features and advantaoes'willmore clearly appear from the detail description given below taken in connection with the accompanying `sheet of drawingsv which, -form a part of this specification.

In the drawings Fig. 1 is a vertical View, largely diagrammatical with some vparts shown in section, of a system embodying myv improvements in one form. Fig. 2 isla vertical section taken on the line 2-2 of Fig. 1. -f

Fig. 3 is a detail illustrating a modification, and Fig. 4 is a detail section taken line 4 4 of'Fig. 1.

Referring to the drawings 4 represents `a compressor driven by any suitable source of Amechanical energy (not shown for compressing the refrigerating agent'and forcing it out through a pipe 5 connected with pipe 6 by valve 7, the compressed refrigerant passing froml pipe 6 into coils of cooling pipes 8 in a cooling tank or ,condenser 9. To

cool and liquefy the refrigerant in the coils 8 coldv Water is sprayed down over the coils 8 from a pan 10, the water being collected in a pan 11 at the bottoni and withdrawn on the therefrom through pipe 1.2. The liquefied v20 in the upper part of the chamber. The Acompressed and liquefied refrigerant after v passing through pipes 16 and 19`and coil 20 enters pipe 21 through which the refrigerant,

still under high pressure', passes to the expansion valve 22 which may be of any wellknown or suitable kind. Fro'm the expansion valve 22 the refrigerant passes through pipe 23 into refrigerati-,ng coils 24, in a tank l25.

In the illustration shown the tank 25 is filled with brine 26 adapted to be cooled by the refrigerant 1n thepi e coils 24. A pump 28 is connected to the ottom of the tank 25 by pipe 29 for withdrawing the cooled brine from the tank, whence itis pumped through refrigerating pipes elsewhere and. returned to the tank 25 through pipe 3(7). The tank is tion through the coils 24* wherein the refrigerant is gradually and largely vaporized by the absorption-of heat from the incoming brine, the refrigerant passes out through plpe 32 and into the upper part/,of the chamber 17. The upper portion of the chamber 17 is connectedv to the suction side of the compressor by pipe 33, valve 34 and pipey 35, a scale trap being included at 36. Due to the expansion and volatilization of the refriger-` ant in the coils 24 and the suction action of the compressor on the chamber 17, the volatilized refrigerant travels through the coils 24 and into the chamber 17 at fairlyhigh velocity and with an entrained liquid carried, thereby, enterst e enlarged space within the chamber .17 where the liquid has an opportunity to become separated and fall downward, while the gaseous refrigerant rises and passes by the pipe 33 to the suction of the compressor. The separating effect is enhanced as shown in Fig. 4 by the entrance of the pipe 32 into the chamber 17 in a tangential direction and the imping'ing of the'gas in rotation within the chamber 17 against spiral grooves so disposed as to dei-lect it downward.

For certain installations the use of alcohol, ether, ethyl for methyl chloride methane, prol pane or but-ane or the like, as refrigerant `in the compressor.

has certain advantages over the usel of ammonia even though the lubricantused in the compressor is more easily removed from the latter, and as my system is especially designed for use of the' former it will be so described. T hc refrigerant being com ressed in the compressor carries away with 1t more or less of the-lubricating oil necessarily used less soluble in the refrigerant which is thoroughly liquefied in the coils 8 passes therethrough with the refrigerant into the receiving tank 13 and so on through the pipes 16, 19, 20, 21 and 23 into the expansion and coolin coils 24., Here, duetto the vaporationof re rigerantthe remaining liquid refrigerant becomes more and more saturated with lubricant, the oil laden refrigerant tending to settle and collect in the lower coils 24. This considerably decreases the efficiency of thel system since it tends' to retard the circulation, interferes with the free evaporation of the refrigerant and increases the boiling point f of the mixture. Normally the refrigerant is vaporized gradually throughout its travel up through the various layers of horizontal pipe coils 24, and in order that any entrained. oil

The oil being morelor shall be carried along with it and out into i the chamber 17, I provide in the pipes v24 a plurality of traps to prevent liquid in the the mechanical action thereon of the vapol rized refrigerant. To provide such trapsthe l adjacent up er and lower respective horizontal layers of with the lower portion of each loop extending below the level of the respective lower layer pipes and upper portion of the loo extending above the level of the respective upper layer ofpipes. That is, for example, taking the adjacent pipe layers A and B, the loop 40 connecting the same has a portion C extendpipesare connected by loops 40 ing below the level of lower pi e layer B and it also has a portion D exten ing above the level of 'the pipe layer A. In this manner traps are provided comprising depressed portionsv adjacent the -exit ends of the Various layers of the pipes and raised portions adjacent the entrance ends of the various layers of the pipes. The oil containing liquid lubricant will irst collect in the lower layer and run into the trap E. The rush of refrigerant through the apparatus forces this up over the loop and it is prevented from running back by the raised trap F. It then readily-flows along the second layer of pipe coils and is caught in the trap G, which not only tends to prevent any backward flow but also serves as a trap, like the trap E, to cause the rush of volatilized `refrigerant to force the liquid up over the loop into the next pipe layer. This action is repeated through the remaining layers of pipe coils until finally any unvolatilized refrigerant with lthe liquid lubricant is carried over4 the upwardly extending trap Hand into the chamber 17. By reason of the tangential induction of the pipe 32 into 'the chamber 17 and the s iral-grooves lubricant ladenrefrigerant settles to the bot'- tom of the chamber.` Here, by reason of the through the pipe 19, substantially all -of the remaining liquid refrigerant is distilled from the lubricant and passes upward and7 off throughr ipe 33, leaving a layei` of oil in the bottomo t of the refrigerant therein.

The height of liquid collected in the bottom-of thechamber may. be observed by a e chamber with very little, lif any,

iven a l lrelatively warm liquid refrigerant passing be transferred back to the compressor by a pipe connection 42 through a valve 43 for regulating the fiow. A layer of liquid lubricant should be retained in the bottom of the chamber to provide a seal to prevent refrigerant from escaping to the compressor through the pipe connection 42. Therefore the valve 43 is only opened to permit part o'f the collected lubricant to pass into the compressor. This may be done from time to time by hand by opening the valve when the liquid level appears near the top of the gage glass 4l and permitting the lubricant to run into the compressor until the liquid level is near the bottom of the gage glass when the valve should be closed.

I prefer, however, to accomplish this automatically and for this pur ose I have shown the lower end of the cham er provided with a bulge at 44 in which is located a thermostat 45 adapted, when the temperature in the oil layer increases above a certain point, to close an electrical circuit 46, 47, 48 through a source of electric current 49 and an electro-magnetic device 50 which opens t-he valve 43 to permit the oil to run back to the crank case of the compressor. When the liquidflevel in the chamber drops to such a point that the liquid around the thermostat contains a substantial amount of refrigerant the temperature thereat will be lowered and the electrical circuit opened to close the valve. In order to insure that the lubricant will flow through the pipe 42 to the crank case ofthe compressor I connect the crank case chamber, by pipe 51y with the suction end of the compressor through a check valve 52 which equalizes the ypressure at both ends but prevents any flow through the check valve to the crank case of the compressor. The compressor is also shown provided with the usual cross-over by-pass connections 53 and 54. The upper portion of the collecting chamber 17 and the pipes .21,- 32 and 33 may be insulated with suitable heat nsulatingl material as indicated in dotted mes. f

In Fig. 3 I have illustrated a further modifA fication for automatically regulating the flow of lubricant from the collecting chamber through the pipe 42 to the compressor crank case. As there shown a float 55 rests on the liquid in the chamber, which float is-con-l nected to a spindle 56 connected to one end of` a' lever 57 the otherl end of the lever being connectedto a link 58'adapted to openl and close the valve 43. When the rich liquid lubricant in the chamber rises to a predetermined height, the iioatthrough spindle 56,

lever 57 and link 58 causes the valve to open and permit the lubricant to flow into the crank case through the pipe'42. When the liquid drops below, the predeterminedlevel the float closes the valve. Y y

WhileI have described my improvements in great detail and withrespect to a preferred form thereof, I do notdesire to be limited to such details or form since many changes and modifications may be made and the in- -ventionfembodied in widely different forms without departing from' the spirit and scope thereof in its broader aspects. Hence I de sire to cover all forms and arrangements coming withinithe language or scope of anyl one or more of the appended claims.

y What I claim as new and desire to secure by Letters Patent, is:

l. In the method of recovering'lubricant from the refrigerant in a refrigerating system wherein the refrigerant is compressed and liquefied in, onev part of the system and is caused to vaporize in' the refrigerating part of the system and the'lubricant is soluble .in the refrigerant, the step .which consists in transferring heat from the. compressed 'refrigerant to lubricant laden refrigerantI leaving the refrigerating part of the system to distill the refrigerant from the lubricant.

2. In the method of recovering lubricant from the refrigerant in a refrigerating system wherein the refrigerant is compressed and liquefied in one part of the system and is caused to vaporize in the refrigerating part of the system in which it-passes in a general upward direction through layers of pipes one above another in a locality to be cooled, land the lubricant is soluble in the refrigerant, the

step which consists in causing the refrigerant A vaporLin said pipes to entrain and by mechanical action carry out of said pipes the mixture of refrigerant and lubricant vafter said mixture has been rendered rich in lubricant by the progressive vaporization of the refrigerant contents of the mixture in the several layers of pipes in the locality to be cooled.

3. In the method of recovering lubricant from the refrigerant in a refrigerating system, wherein the refrigerant is compressed and liquefied in one part ofthe system and is caused to vaporize in the refrigerating part of the system in which it passes upwardly through layers of pipes in a localityl to be cooled, and the lubricant is soluble in the re-l frigerant, the steps which consist in causing the refrigerant vapor in said pipes to entrain and by mechanical action carry out of said pipes the liquid lubricant therein, and in lia transferring heat from the compressed refrigerant to the lubricant laden refrigerant leaving said pipes to distill and. separate the refrigerant fromthe liquid lubricant.

4. In the method of recovering lubricant from thev lrefrigerant in a refrigerating system wherein the refrigerant is compressed and liquefied in onepart of the system and is caused to vaporize inthe refrigerating part of the system in which it passesthrough pipes in a locality to be cooled, and the lubricant is soluble, in the refrigerant, the step which conf sists in causing the refrigerant vapor in said pipes to entrain and by mechanical action carry out of said pipes the mixture of refrigerant and lubricant after said -mixture has been rendered rich in lubricant by the. progressive vaporization of the refrigerant contents of the mixture in successive pipes in the refrigerating part of the system.

i 5; In-the method of recovering lubricant from the refrigerant in a refrigerating system, wherein the refrigerant is compressed and liquefied in one part of the system and is caused to vaporizein the refrigerating part of the system in which it passes through pipes in a locality to be cooled, and the lubricant is soluble in the'refrigerant, the steps which consist in causing the" refrigerant vapor in said pipes to entrain and by mechanical action carry out of said pipes the liquid lubri- `cant therein,and in transferring heat from the com ressed refrigerant-to the lubricant laden re rigerant leaving said pipes todistill and separate the refrigerant from the liquid lubricant. v u f -6. A refrigerating system having in com bination means for compressing and liquefying a refrigerant, a series of cooling pipes in which theliquid refrigerant is permittedl to vapori'ze andvpass in a general-upward directiolrin the pipes to effect cooling, said pipes havmg traps therein to prevent liquid therein from running down counter to the movement of vaporized'refrigerant in the pipes, where- "by liquid lubricant in the pipes is forced upwardly through the pipes and out thereof by i the vaporized refrigerant, and means connected between said cooling pipes and compressing means for collecting liquidl leaving said pipes.

7. A refrigerant system having in combination means for compressing and liquefying arefrigerant, a series of substantiall horizontal la ers of cooling pipes in whic the liquid re rigerant is permitted to vaporouslayers of the pipes.

ize and pass in a general upward direction in the p1pes to effect cooling. said pipes having traps therein to prevent liquid therein from running down counter to the movement ofvaporfzed refrigerant in the pipes, whereby liquid lubricant in the pipes is forced upwardly through. the pipes and out thereof by the vaporized refrigerant, and means conev nected between'` said cooling pipes and com-- Aing a refrigerant, a series of cooling pipes in i which the liquid refrigerant;isupermitted to` -v vaporiz and pass-ina general upward di- ,'rection in the pipes'l to effect cooling, said pipes having traps therein to prevent liqiud -refrigerant is distilled vfrom the lubricant in said collecting means.

9. A refrigerating system having in combi nation means for compressing and liquefyliquid refrigerant is permitted to vaporize to effect cooling, means connected between Said cooling pipes and compressingmeans for co1- lecting 1i uid leaving said pipes, and means for transferring heat from the compressed -ing a refrigerant, cooling pipes in which the refrigerant i" the liquid in said collecting means to-distill refrigerant'from the 4lubricant therein.

10. A, refrigerating system havin bination means for compressing an liqueqing a refrigerant, a series of substantia y horizontal layers of cooling pipes in which in coml i the liquid refrigerant is permitted to va orize and pass in a general upward direction in the pipes to eect cooling said pipes having traps therein to prevent liquid therein from running down counter to the movement of vaporized refrigerant in the pipes, whereby liquid lubricant in the pipes is forced upwardly through the pipes and out there-of by the vaporized refrigerant,and means con# nected between said cooling pipes and compressing means forcollecting liquidl leaving said pipes, said traps comprising loopsvin said pipe, said loops connecting adjacent upper and lower layers of pipes respectively with the lower portion of the loop extending below the level of the respective lower layer.

of'pipes and the upper portion of the loop extending above the level of the respective upper layer of pipes. i 11. A refrigerating system having in combination means for compressing and liquefying a refrigerant, a series of substantially horizontal layers of cooling pipes in which the liquid refrigerant is permitted to' vaporize and pass in a general upward direction. in the pipes to effect cooling, said pipes having traps therein to prevent liquid therein from running. d own counter to the movement of vaporized refri erant in the pipes, whereliy. `liquid lubricant in the pipes is forced upwar ly through the pipes and out thereof by the vaporized refrigerant, means connected between said cooling plpes andA compressing means for collectlng l1 uld'leavlng said plpes,

and means for trans errln heat from the compressed refrigerant to t e liquid in said ,c

collectin means to distill 12- A refrigerati@ systeni havia arc-0in;

bination means forcompressing an 1iquefy- .refrigerant from .the lubrlcant therein.

i ing a refrigerant, a series of substantiall horizontal layers of cooling pipes in whic the liquid refrigerant is permitted to vaporize and pass in a general upward direction in the pipes to effect cooling, said pipes having traps therein to prevent liquid therein from running down counter to the `movement of vaporized refrigerant in the pipes, whereby liquid lubricant in thepipes is forced upwardly through the pipes and out thereof by the vaporized refrigerant, means connected between said cooling pipes and compressing means for collecting liquid leaving said pipes, means for transferring heat from the compressed refrigerant to the liquid in said collecting means to distill refrigerant from the lubricant therein, said last mentioned 'means comprising a pipe in the collecting means through which the compressed refrigerant passes, and means whereby the vapor .and liquid entering the collecting means 1s glven a whirling mot-ion about said pipe to effect more rapid transfer of heat.

13. A refrigerating system having in combination means for compressing and hquefying a refrigerant, a series of substantlally horizontal layers of cooling pipes 1n which the liquid refrigerant is permitted to vaporlze and pass in la general upward direction 1n the pipes to effect cooling, said pipes having p traps therein to prevent liquid therein from running down counter to the movement of vaporized refrigerant in the pipes, whereby liquid lubricant in the pipes is forced upwardly through the pipes and out thereof by the vaporized refrigerant, means connected between said cooling pipes and.compress1ng means for collecting liquid leaving said pipes,

1' means for transferring heat from the compressed refrigerant to the liquidl in said collecting means to distill refrigerant from the lubricant therein, and a connection'for transferring lubricant, collected in the collecting means, to the compressing means.

14. A refrigerating system having in combination means' for compressing and liquefyving a refrigerant, a series of substantially horizontal layers of cooling pipes in' which the liquid refrigerant is permitted to vaporize and passin a general upward direction -in the pipes to effect cooling, said pipes having traps therein to prevent liquid therein from running down counter-to the movement of vaporized refrigerant in thefpipes, whereby liquid lubricant in the pipes is forced up wardly through the pipes and'out thereof b'y the vaporized refrigerant, means'connected between said cooling pipes and compressing` means for collecting liquid leaving said pipes, means for transferring heat from the compressed', refrigerant to the liquid in said collecting means to distill refrigerant from thel lubricant therein, a connection for transfer-v ring lubricant, collected in the collecting rmeans, to the compressing means, and means automatically re ulating the flow of lubricant through sai connection.

15. A refrigerating system'having in comh liquid lubricant in the pipes is forced upwardly through the pipes and out thereof by the vaporized refrigerant, and means connected between said cooling pipes and com7 pressing means for collecting liquid leaving 'said pipes,A said collecting means including an elongated vertical chamber, the lower portion of which is of reduced cross section and heating pipes therein through which the compressed refrigerant passes on its way to the Y cooling `pipes to distill refrigerant from the lubricant in said collectingmeans, said heat. ing pipes being located in the upper portion of said chamber and having a leg extending down into the reduced portion thereof.

16. A refrigerating system having in combination means for compressing and liquefying a refrigerant, a series of substantially horizontal layers of cooling pipes in which the liquid refrigerant is permitted to vaporize and pass in a general upward direction in the pipes to effect cooling,said pipes having traps therein to prevent liquid therein fromrunning down counter to the movement of gated vertical chamber, the lower portion of which 1s of reduced cross section'and heating pi es therein through which the compressed re rigerant passes on its way to the cooling pipes tol distill refrigerant from the lubricant in said collecting means, said heating pipes being located in the upper portion of said chamber and'having a leg yextending downiinto the reduced portion thereof, and

a connection for transferring lubricant collected in the collectingl means to the compressing means, and means automatically regulating the iow of lubricant through said connection.

. .17. A refrigerating'systeml having in combination means for compressing andliquefying a refrigerant, cooling means in which the liquefied refrigerant is permitted to vaporizeto effect cooling, and means connected f between said vaporizing means and compress-` ing mea-ns for Vcollecting liquid leaving said vaporlzmg means, sald collecting means comprising a chamber, means for transferring 'heat from the compressed refrigerant to the. liquid in said chamber to distill refrigerant from lubricant' therein, said last mentioned means including a pipe in the chamber throughwhich the compressed refrigerant passes on its way to the vaporizing means, and means whereby the vapor and liquid entering the collecting means is given a whirling motion about sald pipe to effect f a more rapid transfer of heat.

18. A. refrigerating system havin in combination means for compressing an liquefy-v ing a refrigerant, cooling means in which thel liquefied refrigerant is permitted to vaporize to effect cooling, and means connected between said vaporizing means and compressing means for collectingliquid leaving said vaporizing means, said collecting means comprising a chamber and means for transferring heat from the compressed-refrigerant to the liquid in said chamber to distill refrigerant. from lubricant therein, and a connection for transferring lubricant collected in .said collecting means to the compressing means.

19. A refrigerating system havino in combination means for compressing andJ liquefying a refrigerant, cooling means in which 'the liquefied refrigerant is permitted tovaporize to effect cooling,and means connected between said vaporizing means and compressing means for collecting liqmd leaving said -vaporizing means, said collecting means com- Y prising a chamber and means for transferring heat'from the compressed refrigerant' tothe liquid in said chamber to distill refrigerant from lubricant therein, a connection for transferring lubricant collected in said collecting means to the compressing means, and means automatically regulating the flow of lubricant through said connection.

20; A. refrigerating system having in com-` bination means for compressing and lique fying a refrigerant, cooling means in which the-liquefied refrigerant is permitted vto vation o porize to effect cooling, and means connected between said vaporizmg means and means for collecting liquid leaving said vaporizing y means, said collecting means comprlsing an elongatedvertical chamber, the lower portion of which is of reduced cross-section and heating pipes therein through vwhich the compressed refrigerant passes on its way to the cooling pipes to distill refrigerantV from the lubricant in said collecting means, said heating pipes bein located in the upper porsaid cham er and having a leg extending down into the reduced portion therec 'n 5 21. A refrigerating system having in comreduced portion t ereof, an a connection for transferring lubricant collected in the collecting means to the compressing means.

In testimony whereof I have signed my name to this specification. g y

THOMAS M. GUNN.

i 1st-1 Y bination means for compressing and lique-A fymg a refrigerant, cooling means in which.

the liqueed refrigerant is permitted to va-y porize to effect cooling, and means connected l 

